// 链表
let a = {val:'a'} //链表头
let b = {val:'b'}
let c = {val:'c'}

a.next = b
b.next = c
//遍历链表
let p  = a
while (p){
  console.log(p.val)
  p = p.next
}
//插入
const e = {val:'e'}
a.next = e
e.next = b
//删除e
a.next = b